Tamper-evident life vest package

ABSTRACT

In general, the invention is directed to methods and articles for inspecting aircraft life vests using radio frequency identification technology (RFID). In one embodiment, a tamper evident, RFID-enabled package is described, the package containing a life vest. Methods of manufacturing the package are also described.

This application claims the benefit of U.S. Provisional Application No.60/889105, filed Feb. 9, 2007, and U.S. Provisional Application No.60/863821, filed Nov. 1, 2006, and U.S. Provisional Application No.60/744185, filed Apr. 3, 2006.

TECHNICAL FIELD

The invention generally relates to tracking and managing life vests onaircraft, and more specifically to a tamper-evident life vest packageconfigured to be inspected by an RFID reader, and methods ofmanufacturing the same.

BACKGROUND

Aircraft that fly a certain distance over water are often required tohave a life vest for every person on board that aircraft. To ensure thepresence of each required life vest, at least two types of inspectionare often conducted. The first is a pre-flight inspection, which istypically made by the flight attendant or gate mechanic. This pre-flightinspection confirms the presence of life vests under each aircraft seator where life vests are otherwise required. If any given life vest ismissing, the life vest is replaced or the seat is not used on theflight. The second is a more comprehensive inspection, which is made bymechanics as part of routine maintenance. In this type of inspection,the mechanics or other authorized personnel not only inspect the lifevests for their presence but also their expiration dates.

Most aircraft life vest inspections are done manually, by a person orpersons visually confirming the presence of a life vest where one isrequired, then, if necessary, manipulating the life vest to ascertaininformation concerning the life vest, such as to check the expirationdate or other information. This information is often printed uponlabels, the life vest itself, or the life vest's packaging.

SUMMARY

In general, the invention is directed to methods and articles forinspecting aircraft life vests using radio frequency identificationtechnology (RFID). As one example, computer-implemented RFID-enabledinspection devices (for example computers or personal digital assistantswith RFID functionality) are described that provide graphical userinterfaces to assist in facilitating the inspection. In a furtherexample, the graphical user interface renders a representation of aportion of the aircraft, associating visual indicia with areas on theaircraft where life vests are expected to be located.

As another example, methods are described whereby an employee of anairline, or another individual charged with inspecting an aircraft'slife vests, loads information concerning the aircraft into his or herinspection device. The inspector then proceeds to move within theaircraft and interrogate RFID tags located upon life vests or life vestpackaging, and possibly RFID tags that provide proximity information. Insome embodiments, the proximity information is derived from the streamof life vest RFID tag information captured during the interrogation suchthat no proximity RFID tags are necessary.

This captured information is compared to the information concerning theaircraft, and the device identifies any exception conditions that may bepresent. For example, an exception condition may exist when theinspection device does not receive indication of one or more RFID tagswhere a database or other data store indicates that an RFID-tagged lifevest should be located. Additionally, an exception condition may existwhen the inspection device receives information indicating one or morelife vests are expired, soon-to-be expired, or misplaced. The inspectormay then remedy the exception conditions as they arise, or alternativelythe data defining the exception conditions may be used to generate anexception report which can be used at a later time to remedy anyexceptions.

The RFID-enabled inspection device may contain an output, e.g., adisplay screen, which provides information to the inspector. Thisinformation may include visual representations of the aircraft (orportions of the aircraft), the locations where life vests are expected,and the presence or absence of the life vests. The information may begraphically presented and arranged in a manner that facilitates andsupports the inspector's movement within the aircraft during aninspection.

In certain embodiments, RFID tags may be located upon, within, or withinclose proximity to the life vests (upon life vest packaging, forexample). These tags may be located inside of the life vest. Interiorplacement allows for increased protection for the RFID tag againsttampering and removal. Particularly, placement of an RFID tag on aninterior surface of the life vest protects the tag from environmentalrisks (such as impact, abrasion, picking, chemical attack, or oxidativedegradation).

In another embodiment, the tags may be manufactured and affixed to thelife vest or a package containing the life vest so as to functiondifferently if an individual tampers with the life vest, the package, orthe RFID tag itself. For example, the RFID tag may be oriented on apackage containing a life vest such that upon opening the package, atleast a portion of the RFID tag is compromised, which renders the RFIDtag to function differently than had the compromise not occurred. In oneembodiment, the RFID tag ceases to function entirely upon compromise.Alternatively, the RFID tag supplies certain data upon interrogation toreport the tampering.

A variety of approaches to placing an RFID tag on the interior of a lifevest are described. Examples include having a non-adhered, non-securedRFID tag inside the life vest that can freely move within the life vestor device. Alternatively, adhesives are described that work well on theinterior surfaces of life vests. Finally, non-adhesive based methods ofsecuring the RFID tag to the interior of a life vest are described.These include, for example, the use of ultrasonic welding.

In one embodiment, the invention is directed to an article comprising asealed package made of a membrane; a personal floatation device disposedwithin the sealed package; an opening mechanism for opening the packagealong a pre-defined area of the membrane; an RFID device comprising aflexible substrate having an antenna and an integrated circuit disposedthereon; wherein the RFID device is affixed to the membrane of thesealed package to span an area of the package along the pre-defined areaof the membrane so that opening the sealed package will mechanicallycompromise a portion of the flexible substrate.

In another embodiment, the invention is directed to a method ofmanufacturing a tamper-evident package made of a membrane comprisingplacing a life vest inside of the package; determining the package'stear path; and affixing an RFID device comprising a flexible substratehaving an antenna and an integrated circuit disposed thereon to themembrane such that part of the flexible substrate is on both sides ofthe tear path so that when the package is opened along the tear path theflexible substrate is mechanically compromised.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating a high-level view of a useroperating a mobile RFID-enabled inspection device to inspect for lifevests under aircraft seats.

FIG. 2 is a flowchart showing one example manner in which an airlinecould receive RFID-tagged life vests and place them on aircraft.

FIG. 3A is a block diagram illustrating a high-level view of an exampleRFID-enabled life vest inspection system as could be utilized, forexample, in inspecting aircraft

FIG. 3B is a block diagram illustrating a high-level view of an exampleRFID-enabled vehicle inspection system.

FIG. 3C is a block diagram illustrating a high-level view of a lesscentralized example RFID-enabled life vest inspection system.

FIG. 4 and FIG. 5 are flowcharts showing an example inspection using theRFID-enabled life vest inspection system.

FIG. 6A through 6C are flowcharts showing example techniques in whichinspection device location information could be ascertained.

FIG. 7 is a view of an example plane and associated seatingconfiguration.

FIG. 8 through 10 are example screen shots of a user interface.

FIGS. 11 and 12 are flowcharts illustrating an example manner in whichuser interface module might function.

FIG. 13 is a flowchart illustrating an example manner in which a usermay generate certain components of an aircraft profile by interactingwith user interface module.

FIG. 14 is a drawing of an example life vest with multiple RFID taglocation configurations.

FIG. 15 shows example layers of an RFID tag, life vest membrane, andadhesive layer.

FIG. 16 is a modified flowchart showing a life vest being folded andplaced into a life vest package.

FIG. 17 is an example view of a life vest package.

FIG. 18A through 18D are diagrams showing repeating RFID tags withalternative tear propagation configurations.

FIGS. 19A and 19B are views of an RFID tag affixed in various locationsto a life vest package.

FIG. 20A through 20H are graphic illustrations in support of certaintesting methodology and results.

FIG. 21 is a diagram illustrating how a user might interrogate a profileinterrogation point within an aircraft to receive a vehicle's profile.

FIG. 22 is a flowchart showing a high-level process that may be used topopulate on-vehicle storage and retrieval system with a vehicle'sprofile.

FIG. 23 is a flowchart showing one example manner in which a user mayinspect a vehicle where the vehicle's profile has been retrieved from anon-vehicle profile storage and retrieval system.

DETAILED DESCRIPTION

FIG. 1 is a diagram illustrating a high-level view of a user operating amobile RFID-enabled inspection device to inspect for life vests underaircraft seats. Inspector 14, also referred to as user 14, usesinspection device 10 to interrogate an RFID tag (or label) 15 attachedto one or more life vests 13 to determine whether the life vests areproperly located under aircraft seats 12 contained within an aircraft.In this example, inspection device 10 includes screen 3, which providesvisual feedback and possibly directions to user 14. In one embodiment,and as described in greater detail below, user 14 uses inspection device10 to inspect the aircraft for present, altered, missing, moved,improper, expired, or soon-to-be expired life vests (or some subset ofthis list). Though described herein with respect to using RFIDtechnology to inspect for life vests on an aircraft, the same techniquesmay be used to inspect other vehicle types, such as boats, tankers,trains, automobiles, trucks, busses, emergency vehicles (fire trucks,police cars, ambulances), space crafts, motor bikes, bicycles, or anytype of vehicle for items such as life vests, fire extinguishers, smokeor fire detectors, seats, emergency slides, safety equipment, signs andplacards, oxygen-generating canisters, oxygen tanks, electronicequipment (e.g. entertainment equipment) or any item beingtime-sensitive (e.g. having an expiration, maintenance, and/orcalibration date), a specific serial number, a specific location orquantity required on a vehicle. A vehicle, as the term is used herein,refers to any apparatus by which someone travels or something is carriedor conveyed. Types of vehicles include those mentioned above, but alsoinclude aircraft, spaceships, satellites, and submarines.

User 14 may be any authorized personnel charged with inspecting anaircraft for the presence or absence of life vests. The specific role ofuser 14 usually depends on the type of inspection being conducted. User14 may go through an authentication process to ensure he or she isauthorized to make the inspection, or to at least record whichparticular user was facilitating the inspection. This could be done byinterrogating an RFID tag associated with the user him- or herself, viafor example an identification badge. There are generally two types ofroutine life vest inspections (there may of course be ad hoc inspectionsto address other needs). The first inspection type is a pre-flightinspection, which is typically made by the flight attendant or gatemechanic. This pre-flight inspection confirms the presence of the lifevest under the seat or where otherwise expected. If a life vest ismissing, the inspector provides a new life vest or the correspondingseat is not used on the flight. The second type of inspection is a morecomprehensive inspection made by mechanics or other personnel as part ofroutine maintenance. At these inspections the life vests are inspectednot only for their presence but also their expiration dates.

Inspection device 10 represents a portable device having an RFIDantenna, RFID circuitry for interrogating RFID tags, and an internalprocessor or other computing device. The RFID device produceselectromagnetic fields for interrogating (i.e., communicating with) RFIDtags 15 attached to life vests 13. Inspection device 10 includesinspection device screen 3, which may be any type of screen that conveysvisual information to a user, but in preferred embodiments is a liquidcrystal display, or light emitting diode-based display. Screen 3provides visual information to user 14. This information may includeinformation about the inspection, such as which life vests 13 have beenidentified. It may also direct user 14 to inspect a certain row, orre-inspect a row after an exception condition is identified. Screen 3displays, in part, a graphic user interface to user 14, whichfacilitates or assists in facilitating inspection of the aircraft.Inspection device 10 may also include a speaker or other audio devicecapable of signaling and communicating with user 14. The audio deviceprovides useful information to inspector 14 to facilitate inspection ofthe aircraft.

Inspection device 10 generates exception reports 2. Exception reportsmay be graphically rendered on screen 3 or printed on paper, orotherwise may be any visual or audio indicia that indicates a possibleexception condition (e.g., the absence of one or more life vests 13, orthe presence of one or more life vests 13 that are not consistent withaircraft records (for example, where the life vest is expired, moved, orhas been tampered with)).

In one embodiment, inspection device 10 provides two general types ofreports: real-time and summary. Real-time reports include the feedbackpresented to user 14 in the course of an inspection. Real-time reportsmay, for example, show the status of each row/seat for which a life vesthas been located, as well as seats for which an exception conditionexists warranting manual follow-up by inspector 14, such as a missing orexpired life vest. Real-time reports are primarily consumed by inspector14. Summary reports contain basically the same type of information asreal-time reports, but are generated at the conclusion of theinspection. They are generally archived as part of an airplane profile,as will be discussed further, and may be more appropriate forconsumption by, for example, regulatory agencies or management.

Ideally each life vest 13 on an aircraft is marked with an RFID tag 15.RFID tags 15 can be selected based on the appropriate frequency. In oneembodiment, tag 15 functions at a frequency considered for aerospaceapplications (e.g., either 13.56 MHz or 915 MHz). However the inventionis not limited to these frequencies. The selected frequency may extendor limit the read range of inspection device 10. For example, oneembodiment described below involves interrogating life vest containingareas one row at a time. At limited read ranges, it may be necessary tointerrogate one seat at a time by aiming inspection device 10 at anindividual seat, or at multiple seats as the range allows. A preferredtag for one embodiment might be based on frequencies that give greaterread range. Although passive tags are mainly considered with respect tothe example description of this invention, an alternative is to useactive tag technology, where the RFID tag includes its own power source.If an active tag system were used, the read ranges could be sufficientto make a complete inspection of the total aircraft from one location.

Different methods may be used to store data on RFID tags 15 associatedwith life vests 13, and the specific data recorded can be tailored tothe needs of the airline and life vest manufacturer. In someembodiments, the basic data defined by EPCGlobal™ Class-1 Generation-2Ultra High Frequency RFID Protocol can be used. This is a protocol forhow data is laid out and collected in the RFID tag. Other protocolscould also be used. In this example, the data may include a uniqueidentifier, manufacturing information (manufacturer, place ofmanufacture, time of manufacture, and other related information), andother data that defines and further identifies the life vest (forexample, type of vest, or maintenance history of the life vest (such atservice dates and repair type, if applicable)).

In some cases, data associated with the life vest is stored on the RFIDtag itself, and if the data set is small, a 96 Kbit chip will besufficiently large to handle most of the data. Alternatively, the dataconcerning a life vest may be held in a central computer system withunique identifier numbers assigned to the RFID tag 13 on each vest. Asubset of this information can be associated with a particularairplane's profile and provided to inspection device 10 before anaircraft is inspected, as will be described further.

In various embodiments, location information of inspection device 10, atthe point of inspection, herein referred to as inspection devicelocation information, is useful at the time of interrogation or later inorder to identify a negative situation, namely the absence of a lifevest 13 in its expected location (expected location being defined as thedata set representing the life vests' expected location information).Inspection device location information may be used to determine theexpected state for each seat or other discreet area of an aircraft.Expected state information defines, for example, what life vests areexpected in the coming set of interrogations. For example, when user 14interrogates the twentieth row of an aircraft, the inspection devicelocation information could be used to automatically look up thetwentieth row in a database. This look up could retrieve informationshowing that the twentieth row contained two seats, and the two seatshave life vests with RFID tags that having unique alphanumericidentifiers of A385 and E583. Further information retrieved could showthat A385 has an expected location of seat 20B and an expiration date ofMar. 10, 2015, and E583 which has an expected location of seat 20A andan expiration date of May 15, 2017. In this example, the expected stateinformation for the discreet inspection event comprises: the fact thatthe row contains two seats, the unique identifiers of the RFID tags onthe life vests, the expiration information, and the expected locationinformation associated with each life. If the interrogation, orinspection, of the twentieth row reveals a data set that does not matchthe expected state information, the entire row may be first marked assuspect. Depending on the specific information that is retrieved duringinterrogation, however, some of the seats may be deemed to beacceptable, and thus de-marked. This would be the case, for example,when there is row of several, say three, seats and two of the seatsmatch expected state information. Only the third seat would be marked assuspect, which via the user interface displaying reports 2 on screen 3,would alert inspector 14 to follow-up on this seat. In other words, at ahigh level, determining whether a life vest is absent is a function ofcomparing the data set of an inspection event (for example, theinterrogation of a row) to expected state information for that row. Thesame is true for inspection events that are seat-by-seat, or possiblyaisle by aisle, or plane by plane. If a row has one seat, the expectedstate condition would be defined as such, and the comparison betweenwhat life vests are present and what are expected to be present wouldonly involve one life vest. The particular scope of an inspection eventis an implementation-specific detail; differing scopes may haveadvantages and disadvantages depending on particulars of theapplication. For example, certain aircraft may be deemed flight-worthyafter an inspection that shows an acceptable number of life vests wereconfirmed, by inspection of their associated RFID tags, to be onboard anaircraft. Or, certain aircraft may be deemed flight-worthy only after aninspection that confirms the proper number of life vests have aseemingly proper distribution throughout the aircraft (they are not allbunched up in a cargo hold in the aircraft's rear, for example). Or, asyet another example, certain aircraft may be deemed flight-worthy onlyafter an inspection that confirms that each life vest of record undereach seat is in fact under that seat. These three examples show varyingrequirements of positional resolution—various techniques or combinationsof techniques may be used to achieve each of these positional resolutionrequirements.

Tests of some aspects of various inspection methods were conducted on aBoeing 737 and 747, a McDonnell-Douglas DC9 and 10, and an Airbus A300.Life vests were installed under seats in five rows of each aircraft.Test results are summarized later in this specification. The testingrevealed instances where, for example, the first seat in the row beinginterrogated was not immediately detected, but seats from adjacent rows(or even further away) were detected. These phenomena may be the resultof metal components in seats, or metal components used in the aircraft,which cause multiple signal paths between the inspection device and theRFID tags. Further, metal structure within and beneath the seats coulddepolarize radio frequency signals. These phenomena are generally termed“multi-path,” and certain techniques described herein take advantage ofthem. The term multi-path refers to any interrogation of an RFID devicewherein the radio frequency traversal path is not direct, and is insteadreflected or deflected off another surface, or whereby another materialtransmits the radio frequency.

Aircraft seats on some aircraft include a metal pan, which may operateas an insulating shield. One approach to successful interrogation of anRFID tag located under an aircraft seat that contains a metal pan is toreflect the radio frequency signal off a conductive surface such as thefloor of an aircraft, thereby taking advantage of multi-path RFIDinterrogation. The path the radio signals must travel when reflected offanother surface such as the floor are generally longer thaninterrogation of the RFID tag directly, so an increase in the radiosignal power of the interrogation device is sometimes helpful, thoughnot always necessary. Of course, the increased power may cause otherRFID tags under other aircraft seats to be successfully interrogated.

Expected state information may exist or be derived at several levels,and each has advantages or disadvantages. Ideally, expected stateinformation is defined for each model interrogation set by inspectiondevice 10. A model interrogation set is defined by the scope of aninspection event. For example, if inspection device 10 is inspecting theaircraft by row (a model interrogation set), expected state informationwould ideally be available by row. An inspection event would be, in thisexample, when the inspector aims inspection device at the row, pulls thetrigger of inspection device 10, and receives feedback that informationconcerning the row has been received by inspection device 10. Suchfeedback might be, for example, an auditory beep, or an update of visualindicia on screen 3. Alternatively, no feedback is needed to define theend of an inspection event. The end of an inspection event could bedefined by protocol if, for example, user 14 merely made sure aninspection event was at least a minimum period of time, say two seconds.

The life vests 13, with attached RFID tags 15, are delivered to eitherthe airline, to be installed on the seats by airline mechanics, oralternatively, to the seat manufacturer who will pre-install life vests13 on the seats 12 before they are delivered to the airline. FIG. 2 is aflowchart showing one example manner in which an airline could receiveRFID-tagged life vests and place them on aircraft.

First, life vests are received by the airline, which have already beenaffixed with RFID tags (2050). As mentioned earlier, the airline mayreceive these life vests already attached to seats, from the seatmanufacturer. Alternatively, the airline may receive the RFID tags andattach them to life vests it already has, or hire contractors to do it.This is called retrofitting RFID tags to life vests. Finally, it will beappreciated that it is not necessary to affix an RFID tag to a life vestitself. Rather, the RFID tag might be affixed to the packaging intowhich the life vest is placed. This technique is described further elseware in this specification.

Next, the airline may inventory the RFID tag associated with each lifevest (2051) and receive back from the RFID tag at least a uniqueidentifier. With this unique identifier, the airline may then update theRFID-enabled life vest tracking system to associate the uniqueidentifier with a location on the aircraft where the attached life vestwill be stored (2052). This location may be, for example, a seat number,which may indicate a life vest is associated with the underside of theseat (a location where life vests are typically stored on aircraft).Information identifying where a life vest is expected to be located istermed a life vest's expected location information. The life vest'sexpected location information may either be stored on the RFID tagitself, or it may be stored in a database elsewhere, or both. Thoseskilled in the art will appreciate that this is an example only, andthat a fully unique identifier may not be necessary, especially if aunique identifier may be derived from the eventual loading of expectedlocation information onto the life vest. In other words, the expectedlocation information may form the basis of a unique identifier, eitheralone or hashed with some other identifier, such as a number or key thatidentifies the particular aircraft.

Finally, after the unique identifiers associated with each life vesthave been associated with expected location information, the life vestsare placed on the aircraft (2053). In a different embodiment, the uniqueidentifiers associated with each life vest may be associated withexpected location information after the life vests have been placed onthe aircraft by, for example, putting the inspection device into a learnmode then stepping through the basic steps of an inspection. Regardlessof point in which life vests are associated with expected locationinformation, once the association is completed, life vests may beinventoried using some embodiments of methods, techniques, and devicesdiscussed further in this specification.

As mentioned, when life vest 13 containing RFID tag 15 is finallyinstalled on an aircraft, the RFID tag 15 and thus life vest 13 may beassociated with a location on the aircraft (the life vest's expectedlocation information). The expected location information is usually datadefining a given seat in the aircraft under which life vest 13containing RFID tag 15 is located, but it could be any information thatdefines a location on the aircraft, such as a seat number or lockerlocation. Life vest 13's expected location information can either bestored on life vest 13's RFID tag 15, or it can be stored in a separatedatabase. For example, the information could be stored in a databasemaintained by the airline, then accessed before or after an inspectionby user 14. Unless otherwise stated, assume for the purposes of examplein this specification that the RFID tags on life vests contain expectedlocation information in the form of seat numbers, and that thisinformation is also, or alternatively, contained within a centraldatabase of the life vest tracking system.

In some embodiments, it may not be necessary to associate life vest RFIDtags with expected location information. Inspector 14 may inspect theaircraft without life vest expected location information ever havingbeen associated with a life vest. This would be the case, for example,if a user supplied the expected location information at the time of lifevest RFID tag inspection. For example, if user 14 aimed inspectiondevice 10 at a row of three seats, user 14 would expect three uniqueRFID tags to respond to the interrogation. If three RFID tags where notsuccessfully interrogated, user 14 would know there was an issue thatrequired further manual inquiry.

This approach may be expedient, but may also require ensuring thesignals being received by inspection device 10 originate from the RFIDtags associated with the seat or set of seats user 14 is inspecting. Forexample, a problem may arise if device 10 erroneously receives signalsfrom life vest tags under seats in front of or behind the groups ofseats user 14 believes he or she is interrogating. This issue may beaddressed, however, by adjusting the signal strength emanating from theRFID reader and estimating the distance between the inspection deviceand the RFID tag based on the signal strength at which an RFID tagresponds to a signal or ceases to respond to a signal, measuring thesignal strength emanating from the interrogated RFID tag, focusing theaim of radio signals emanating from inspection device 10, notdouble-counting RFID tags already read, shielding, or other approachesfor eliminating or ignoring extraneous signals.

This technique is just one example of how RFID tags attached to lifevests could be inspected without associating each RFID tag with expectedlocation information. Another way would be to perform seat-by-seatinspections in which user 14 places inspection device 10 proximate(e.g., immediately above) each seat such that only an RFID tag under theseat being interrogated would be energized and respond to theinterrogation. In this way, no proximity information need be associatedwith the life vest RFID tag itself in order to confirm the presence oflife vests on an aircraft. However, there may be benefits in associatingexpected location information with each life vest. In particular, suchinformation may be useful as an aid to determining whether a life vesthas been moved, which may be indicative of tampering and requiresubsequent follow-up by user 14.

User 14's flow through the aircraft may be self-directed or may bedirected at least in part by inspection device 10. If the inspection ofan aircraft is directed by inspection device 10, or must be done in anorder pre-specified, this is referred to herein as a defined protocolinspection. A defined protocol inspection might be, for example, whereinspector 14 is required to first inspect the first row, then the secondrow, and so forth. Use of a defined protocol inspection may aiddetermining the location of inspection device 10 at any point during theinspection. This and other techniques for determining where aninspection device is at the point of inspection, will be discussedfurther else ware in this specification. However, in certain embodimentsof the invention, user 14's flow through the airplane is self-directedfor at least the pre-flight type inspection, and does not require adefined inspection protocol. In other words, in these embodiments,inspector 14 may start inspecting aircraft at whatever position he orshe likes, may skip over seats or sections and come back to rows, and soforth, and the inspection is not compromised.

FIG. 3A is a functional diagram showing an example embodiment of avehicle inspection system, particularly an aircraft life vest inspectionsystem, including inspection device 10, host system 30 and RFID tagprogrammer 40, which collectively support aircraft inspections for lifevests 13 containing RFID tags 15. Though described herein with respectto an aircraft, the same concepts described herein could be applied toinspecting items, other than life vests (such as mechanical parts,engine parts, electrical parts, smoke detectors, and so forth), on anytype of vehicle (boats, cars, busses, trains, space ships, satellites,submarines, etc.), as one skilled in the art will readily appreciate.FIG. 3B demonstrates one example manner in which the inspection systemin FIG. 3A could be abstracted to apply to inspecting any type ofvehicle for any type of item or condition on or associated with thatvehicle. Host system 30 may be a centralized computer system that housesa host aircraft profile database 20. Host system 30 also includes userinterface module 32, and administration module 31, which representsoftware modules executed by one or more processors and stored within acomputer-readable storage medium. Both of these software modules may berun on a separate system or over the Internet on web browsers forexample.

All databases described herein may be implemented in many ways, as willbe evident by one skilled in the art. The databases may take a varietyof forms including data storage files, or one or more databasemanagement systems (DBMS) executing on one or more database servers(which may be running on the handheld, or may be connected to thehandheld via a wireless link (802.11x, for example)). The databasemanagement systems may be a relational (RDBMS), hierarchical (HDBMS),multidimensional (MDBMS), object oriented (ODBMS or OODBMS) or objectrelational (ORDBMS) database management system. Databases could, forexample, take the form of a single relational database such as SQLServer from Microsoft Corporation.

Host system aircraft profile database 20 contains aircraft profiles 23.Aircraft profiles 23 may include, for example, information aboutparticular aircraft. This information may include the type of aircraft,a layout of the aircraft, a graphical representation of the aircraftincluding, but not limited to, row, aisle and seat arrangements, storagearea arrangements, and information defining the expected location ofeach life vest 13 on the aircraft, and possibly the life vest inspectionhistory of the aircraft. The aircraft profiles 23 also may includeunique identifiers for each life vest 13, and these unique identifiersmay be associated with a location code (such as a seat number) thatdefines the location within the aircraft where a particular life vest 13should be found if it has not been moved. The aircraft profiles 23 mayinclude notes or procedures useful to inspector 14 at a time ofinspection. Aircraft profile may include code, or scripts, that executeson inspection device 10 and alters default behavior (for example, thescript may say that for a given class of plane, a particular life vestnot being found is not an exception condition). Aircraft profiles 23 maybe located in locations other than a host profile database 20. Forexample, profiles could exist, pre-loaded or otherwise loaded, onto aninspection device, without the use of a central computer. This could beof benefit to operations that have a limited number of aircraft, or areotherwise uninterested in maintaining a centralized host system 30 Theaircraft profile could also exist within, and be retrieved from, an RFIDtag on, within, or in proximity to the aircraft itself. For example, aninspector could scan a profile-containing RFID tag, or cluster of RFIDtags, which contain the aircraft's profile at a particular location inthe aircraft, as further described herein with respect to aircraftinspection system illustrated in FIG. 3C.

Host system 30 also includes user interface module 32 and administrationmodule 31. Administration module 31 allows the importation, updating,reviewing, and reporting of information contained within aircraftprofiles 23. Administration module 31 also facilitates the creation ofnew aircraft profiles, or the elimination and/or archiving of oldaircraft profiles. Administration module 31 interacts with a user viauser interface module 32. User interface module 32 may be enabled via aweb browser, it may be a standalone program running on the same hostsystem as host aircraft profile database 20, or it may be hosted on aseparate system, in a client-server configuration.

Connected to host system 30 is RFID tag programmer 40. RFID tagprogrammer 40 facilitates the inspection and/or programming of RFID tagswithout the use of inspection device 1O. In this example, RFID tagprogrammer 40 contains two software modules, one for reading thecontents of an RFID tag (RFID tag interrogator reader 41) and one forwriting content to an RFID tag (RFID tag interrogator writer 42). RFIDtag programmer 40 contains supporting hardware for these softwaremodules (not shown). RFID tag programmer 40 is used to inspect RFID tagsassociated with life vests and to reprogram life vest RFID tags. Thesame activity may be done in the field, in the course of an inspection,with inspection device 10. However, in some embodiments, it isadvantageous to centrally manage the distribution of life vests, andcentrally maintain information about life vest dissemination. RFID tagprogrammer 40 would be used, for example, if an airline issued lifevests from a central location, at the request of an inspector orautomatically via an inspection device, wherein the request included anRFID tag be generated for a particular location on an aircraft, and thisexpected location information be coded into the RFID tag and also putinto the aircraft profile 23. A user would use administration module 31,through user interface module 32, to program a newly issued RFID tagassociated with a life vest, and update aircraft profile 23. The lifevest would then be issued and placed in its proper location by airlinepersonnel.

In this example, inspection device 10 is composed of software modules 19and one or more local databases 22 (e.g., inspection database 16 andinspection device aircraft profile database 17), which may be organizedin a form suitable for storing and retrieving data within a portabledevice. Software modules 19 interact with databases 22 to determineexpected location information for life vests, expected state informationfor an inspection event, inspection location information of theinspection device 10 at point of an inspection event, and ultimatelywhether a life vest is present, in its proper location, and whether itis expired. Other information or attributes could be checked againstdatabases 22. In other embodiments, some or all of this information isdetermined remotely by host system 30 based on data retrieved from tags15 via inspection device 10. Proximity coordination module 11 determinesthe location of the inspection device at the point of an inspection inone of several ways, as described herein, or it may be deactivated forcertain types of inspections.

User interface module 12 facilitates visual interactions with user 14via screen 3. Particularly, user interface module 12 draws userinterface screens that facilitate user 14's inspection of an aircraftfor the presence or absence of life vests. The specific user interfacesproduced by user interface module 12 are described later in thisspecification.

RFID interrogation module 29 interrogates RFID tags and receivesinformation back from the interrogated tag. RFID interrogation module 29may also utilize a controlled strength of interrogation signal, as wellas in some embodiments sensed strength of the return signal from thetag, to aid in the determination of the actual locations of RFID tagsand their associated life vests. Information concerning theinterrogation generated by RFID interrogation module 29 is placed intoinspection database 16, where it may be analyzed by validation andexception generation module 28.

Inspection device aircraft profile database 17 contains one or more ofprofiles 23, or subset of a profile 23, as primarily stored within hostsystem aircraft profile database 20, and subsequently downloaded ontoinspection device 10 in anticipation of an inspection of life vests onan aircraft. The profile 23 may be accessed by inspection device 10 vianetwork 21. Network 21 could be the Internet, or it could be aninternal, private network. It could be a traditional wired network, orit could be wireless. Inspection device 10 uses network 21 to retrievean aircraft profile 23 from host system aircraft profile database 20. Asmentioned, profile 23 of an aircraft including location information ofthe life vests is preferably done before an inspection of an aircraft,but in one embodiment the data validation and comparison is completedafter the raw data has been gathered via an inspection. In such ascenario, inspection of an aircraft is completed, and then theinspection data is later analyzed in light of aircraft profile 23, andan exception report generated. This functionality may be useful, forexample, where host system 30 was inaccessible at the time an inspectionwas initiated. In another embodiment, the profiles are stored in theinspection device itself, and no host system is necessary.

Data export module 18 facilitates the exportation of data frominspection device 10. Such data could include an updated profile, suchas would be generated if a life vest were reconfigured during the courseof an inspection (for example, the expected location information of alife vest were re-set). Data export module 18 also facilitates theexportation of reports that summarize inspections, and raw data from aninspection for analysis.

Validation and exception generation module 28 contains logic thatassesses inputs generated from other modules, in combination withinformation from the inspection device aircraft profile database 17, anddetermines when life vests are misplaced, expired, or otherwise needfollow-up. Validation and exception generation module 28 sends thisinformation concerning the status of the inspection to inspection deviceaircraft profile database 17, then requests user interface module 12 toupdate its user interface using the new inspection device aircraftprofile database 17 information. More specifically, validation andexception generation module 28 determines or receives inspection devicelocation for an inspection event (if this information is received, it isreceived from proximity coordinate module 11; if this information is theresult of a defined protocol inspection, the inspection device locationinformation at the point of an inspection event is determined internallyto the module). Inspection device location information is used to lookup in inspection device aircraft profile database 17 what information isavailable concerning expected state of an inspection event. The expectedstate information for an inspection event is compared to actualinspection data as placed into inspection database 16 by RFIDinterrogation module 29. From this comparison, the inspection deviceaircraft profile database 17 is updated with information that containsthe status of life vests; particularly those that have been located,those that may have been moved, and those that are expired (the lattertwo categories are marked internally for further follow-up). After eachinspection event, validation and exception generation module 28 requestsuser interface module 12 to update itself with the information newlyupdated into inspection device aircraft profile database 17 concerningthe inspection.

FIG. 3B is a functional diagram showing an example embodiment of avehicle inspection system. Most components are similar to thosedescribed with respect to FIG. 3A. However, the system in FIG. 3Bregards a more general vehicle inspection system, whereby anyRFID-tagged item can be inspected. For example, host system vehicleprofile database 51 contains vehicle profiles 50. Vehicle profiles 50may include information about a particular vehicle. This information mayinclude the type of vehicle, a layout of the vehicle, a graphicalrepresentation of the vehicle including row, aisle and seat arrangements(if relevant to the inspection of that vehicle), storage areaarrangements, and information defining the expected location ofparticular RFID-tagged items on that vehicle, as well as, in someembodiments, the inspection history of the vehicle. The vehicle profiles50 also may include unique identifiers for items, which may beassociated with location codes that define the location within or uponthe vehicle where a particular item should be found. Vehicle profiles 50may include notes or procedures useful to an inspector at the time of,or before or after, an inspection. Such procedures may be part of aninspection protocol, including directions indicating where a vehicleinspection should start or end. Vehicle profile 50 may include code, orscripts, that executes on inspection device 10 and alters defaultbehavior (for example, the script may say that for a given class ofvehicle, a particular item not being found is not an exceptioncondition). Vehicle profiles 50 may be located in, and retrieved from,locations other than a host system profile database 51. For example, andnot illustrated in FIG. 3B, the vehicle profile 50 s could exist,pre-loaded or otherwise loaded, onto an inspection device, without theuse of a central computer. This de-centralized architecture could beattractive to operations having a limited number of vehicles to inspect,or not wanting to incur costs associated with a centralized host system.Other components described with respect to a life vest inspection of anaircraft may operate similarly with respect to inspecting other types ofvehicles for RFID-tagged components or parts, as will be appreciated byone skilled in the art.

Whereas FIG. 3A and FIG. 3B are directed toward a system whereininspection device 10 is at times communicatively connected (via network21) with a centralized host system, FIG. 3C is directed toward anotherexample system which in some embodiments may be more autonomous or lesscentralized. FIG. 3C is a block diagram showing functional modules of aninspection device. As compared with the system illustrated in FIGS. 3Aand 3B, the inspection device 10 in FIG. 3C includes within it certainfunctionality for managing and administering aircraft profiles 23 thatwas previously available in host system 30. Particularly, inspectiondevice 10 in FIG. 3C includes administration module 33. It does notnecessarily provide the same functionality described with respect toadministration module 31 in FIG. 3A and FIG. 3B. Depending onimplementation, administration module 33 includes functionalityassociated with creating, updating, and editing vehicle profiles.

A system similar to that depicted in FIG. 3C may be suited forenvironments where infrastructure requirements of a centralized hostsystem are not practical or undesirable, for example. Further, due inpart to the fact that most or all necessary software components arehoused within inspection device 10, deployment may be simplified. Also,inspection devices may not need be stored within or associated with aparticular vehicle, aircraft, or so forth. Rather, any of a plurality ofinspection devices could be used to inspect any of a plurality ofaircraft for any of a plurality of things or conditions of interest on aparticular vehicle. The same inspection device 10 could one moment beused to inspect a bus, and the next be used to inspect an aircraft. Itwill be appreciated that the same techniques described with respect toan aircraft in FIG. 3C apply to other types of vehicles. For example,one skilled in the art will recognize that a common vehicle inspectionprofile definition standard could be deployed such that any inspectiondevice 10 supporting a particular profile definition standard could beused to receive a vehicle profile, and then use it for inspection of thevehicle. Similarly, standardized, possibly industry-sanctioned oradopted inspection protocols may be programmatically implemented withininspection devices. Then, upon interrogation, inspection device 10 mayreceive information from a vehicle profile-containing RFID chipindicating that the profile being transmitted is, say, for a school busversus an aircraft. The appropriate “school bus inspection protocol” mayalready exist within inspection device 10. Alternatively, inspectionprotocols themselves may be contained within the vehicle profile. Aninspection protocol defines at least some particulars about how aninspection takes place, and examples of inspection protocols arediscussed further below.

Where vehicle profile information is received from on-board means, suchas an RFID tag located somewhere in or on the aircraft and containingthe aircraft's profile, inspections generally start with theinterrogation of the profile-containing RFID tag. FIG. 21 shows acut-away of aircraft wall 35 where user 14 is interrogating profileinterrogation point 34 with inspection device 10. FIG. 21 shows aninterrogation point on a wall of an aircraft, but this interrogationpoint could just as well be at a plurality of locations within theaircraft. For example, one interrogation point might exist for differentsections of a vehicle (main deck, upper deck, etc.), or there may evenbe an interrogation point on each row that returns row profileinformation with every interrogation of a row. After successfulinterrogation, a vehicle profile is returned to the inspection device,and inspection of the vehicle may commence. Profile interrogation point34 may in one embodiment be one or more RFID tags. For the purposes ofdescription and not limitation, many of the examples contained hereinassume that, when the profile is retrieved from an on-vehicle device,the profile comes from an RFID tag located within the vehicle. However,one skilled in the art will appreciate that the profile-containing RFIDtag is just one possible means of holding and providing a vehicleprofile. Rather than an RFID tag, the profile interrogation point 34could instead merely signal an area where inspection device 10 has astrong communication signal with a transponder connected to an on-boardmemory device (a hard drive, flash RAM, etc.). The profile could then bewirelessly communicated to inspection device 10. In other embodiments,there may be no profile interrogation point 34 per se, and instead awireless access point to a network (provided within a suitably equippedaircraft or vehicle), which receives the signal from inspection device10, possibly authenticates the signal via one or more securityprotocols, then responds with the vehicle profile. Such a wirelessaccess point type setup may be increasingly supported as more vehiclesand aircraft include, for example, support for wireless networks.

FIG. 22 is flowchart showing the high-level process that may be used topopulate an on-vehicle storage and retrieval system with a vehicle'sprofile. First, a profile storage and retrieval system is installed onor in the vehicle (22A). The profile storage and retrieval system couldbe as simple as bar codes or other optically-scanned areas that containinformation about the vehicle which is used for that vehicle'sinspection (e.g. the vehicle profile). The profile storage and retrievalsystem could also be an RFID tag, or a cluster of two or more RFID tags,that, when interrogated, provide the vehicle profile. Possible RFID tagsthat could be used as the storage and retrieval system for a vehicleprofile include passive or active, with or without an on-board powersource. RFID tags can range in storage capacity from less than 1024bytes to more than 64,000 bytes. Depending on the size of the vehicleprofile, several RFID chips may be clustered in one area, each providinga portion of the vehicle profile when interrogated by inspection device,which is then assembled by the inspection device to form the wholevehicle profile. As mentioned above, the profile storage and retrievalsystem could be an on-board computing system, in wireless communicationwith inspection device 10. The profile storage and retrieval systemcould also comprise a computer, possibly a modified personal computer,which emulates an RFID tag. The profile storage and retrieval system,though described herein as in wireless communication with inspectiondevice 10, need not, in all implementations, be wireless. For example,the profile storage and retrieval system could interface with inspectiondevice 10 via a universal serial bus (USB) connection, possibly to apassive or active memory device. Among other things, the use of a USBconnection may allow for much higher memory storage capacity. Similarly,other memory storage devices, such as memory cards, could be used. Evenfurther, the profile storage and retrieval system could comprise one ormore RFID tags of different frequency to those used on items, such aslife vests, within or onboard a vehicle. For example, theprofile-containing RFID tag might be a high frequency tag, whereas theRFID tags used to track items might be an ultra-high frequency tag. Oncethe vehicle profile storage and retrieval system is installed, thevehicle may be configured with RFID-tagged parts (22B). In the case ofan aircraft where life vests are to be inspected, this step may includeactually placing the RFID-tagged life vests on the aircraft. Particularconfigurations will vary by application, but this step concludes withRFID tags being situated in the vehicle such that they can beinterrogated. The vehicle profile is then constructed (22C). This may bedone by an application within the inspection device, in one embodiment,or may be constructed in some other computing environment, thentransferred and/or uploaded by some other device. The specifics of whereand how the vehicle profile is constructed are animplementation-specific detail. Some implementations may have aparticular profile that has relevance to a number of vehicles, and theprofile may change only rarely. In such an implementation, the profilestorage and retrieval system could be pre-loaded with an appropriateprofile. If the vehicle's profile changes more frequently (for example,seating is often moved, and the RFID-items to be inspected areassociated with seating), or is more customized (as opposed to moregeneral), inspection device 10 may include software that facilitateschanging the vehicle profile (such as administration module 33). In sucha case, a generic vehicle profile template may exist initially either oninspection device 10 or in the profile storage and retrieval system,which may then be updated by inspection device 10. The template mayinclude a data structure relevant to a type of vehicle, for example.Finally, the vehicle profile is uploaded to the profile storage andretrieval system (22D). The particular mechanism used to upload theprofile is dependant on the technology employed to provide the profilestorage and retrieval system. For example, if the profile storage andretrieval system is an RFID tag or cluster of RFID tags, the RFID tagmay simply be re-written. Alternatively, if the profile storage andretrieval system is a computer system wirelessly connected to inspectiondevice, a security protocol may be invoked before the actualtransmission of the vehicle profile. The security protocol mayoptionally involve an authentication step.

The manner in which the vehicle profile is uploaded and stored withinthe profile storage and retrieval system is yet anotherimplementation-specific detail. Certain implementations may implementstandard encryption/authentication algorithms to authenticate either theinspection device 10 (if the inspection device is uploading the vehicleprofile), or the vehicle profile storage and retrieval system. In oneembodiment, where the profile storage and retrieval system comprisesone, or a cluster of two or more, ultra high frequency RFID tags, eachtag is initialized with a unique identifier, which facilitatesdistinguishing one tag from another, as well as interrogating a clusterof RFID tags, and then assembling their data. If the RFID tag isdestined to be part of a cluster of RFID tags, the unique identifier mayadhere to a schema whereby the identification number itself indicateswhether the RFID tag is part of a cluster, which cluster it is a partof, and how many tags comprise that cluster. This schema may berepresented as follows:

<cluster identification #><RFID tag # within cluster><total # RFID tagsin cluster>

Data written to the RFID tag may be write-locked, which prevents certaintampering efforts by requiring the transmission of a password before thewriting to the RFID tag. Password-supported RFID tags are available inthe marketplace by several vendors. Depending on the sensitivity orcriticality of the data being stored on the RFID tag, the datacomprising the vehicle profile may be encrypted using known symmetric orasymmetric methods. Also, the data may be converted and stored in abinary format, which may not be as readily comprehendible as moretraditional text-storage formats.

Data on the tag itself may be formatted in any manner that can be readby software running on inspection device 10. An extensible markuplanguage format could easily be adapted to describe relevant particularsabout the vehicle being inspected. One exemplary format schema, in thiscase adapted for use inspecting aircraft, is as follows:

Each physical RFID tag that is part of the profile storage and retrievalsystem includes a header containing the following information:

-   -   1) Data map version number. This number indicates which        formatting version is used for storing the vehicle profile data        on the RFID tag.    -   2) Full write indicator bit. Inspection of this bit indicates        whether the RFID tag was written successfully. Among the first        steps in a write operation is to set this bit to false. Then,        writing of the RFID tag commences. A final step is to set this        bit to true. Subsequent reads of the RFID tag confirm the bit is        set to true. If it is not set to true, this may be indicative of        a data integrity issue.

The RFID tag additionally includes a header section containinginformation about the aircraft profile. It may include, for example, thefollowing information:

-   -   1) Aircraft registration number. Unique number for the aircraft        (e.g. N123456).    -   2) User ID. Identifier of the person who wrote the configuration        to the config tag.    -   3) Location. Name entered by user to define the location where        the configuration was written    -   4) Datestamp. Indicates when the aircraft profile was written to        the tag (e.g. Dec. 22, 2006 13:23).    -   5) Config tag full write indicator. This operates in concept        similar to the full write indicator bit, but pertains to the        entire cluster instead of an individual RFID tag.

The remaining memory for the RFID tag may contain the followinginformation, optionally spread across multiple RFID tags as a cluster:

-   -   1) Seat map name. User defined unique name (e.g. A330-300 v2        333)    -   2) Seat map update date/time. When the profile was last modified        and saved on the inspection device.    -   3) Active. Boolean defines if this is the active seat map if        there are multiple seat maps for a given aircraft registration        number.    -   4) Main Deck information. Information defining layout        information regarding aircraft's main deck.        -   a. Number of aisles        -   b. Max number of seats per row        -   c. Total number of seats        -   d. Total number of storage locations        -   e. Inspection start row        -   f. Aisle 1 position        -   g. Aisle 2 position (omit if not needed)    -   5) Upper Deck information. Information defining layout        information regarding aircraft's upper deck, if one exists.        -   a. Number of aisles (if 0, then rest of upper deck info is            omitted)        -   b. Max number of seats per row.        -   c. Total number of seats        -   d. Total number of storage locations        -   e. Inspection start row        -   f. Aisle 1 position        -   2. Aisle 2 position (if not needed)    -   6) Seat Pattern information. This section helps conserve config        tag memory requirements by listing each pattern only once.        -   a. Number of seat patterns-Main Deck. A seat pattern is a            sequence of codes that defines the seat letters in a row            (e.g. ABC-DEF to indicate seats A, B, C, an aisle, and then            seats D, E, F)        -   b. For each main deck pattern:            -   1. Pattern ID.            -   2. Pattern. E.g. A-C˜D-G·H-K.        -   c. Number of seat patterns-Upper Deck. (Omit if none)        -   d. For each upper deck pattern            -   1. Pattern ID.            -   2. Pattern. E.g. ABC˜DEF    -   7) Seat Row information. Specific information about each seat        row segment. Describes similar row sequences of seats as        segments.        -   a. Number of seat segments. A segment is a section of seats            with the same seat pattern.        -   b. For each seat segment:            -   1. Deck Flag. 0 for main deck. 1 for upper deck.            -   2. Pattern ID. (references one of the above patterns)            -   3. From Row #. First row with this seat pattern.            -   4. To Row #. Last row with this seat pattern.            -   5. Grid Row #. Used by internal algorithm.    -   8) Storage information. Defines storage areas on the aircraft.        -   a. Quantity of storage locations.        -   b. For each storage location:            -   1. Storage Name. Defined by user. E.g. Overhead Row 4            -   2. Storage Number. Used by internal algorithm.            -   3. Grid Row #. Used by internal algorithm.            -   4. Grid Column #. Used by internal algorithm.            -   5. Deck Flag. 0 for main deck. 1 for upper deck.            -   6. For each item expected in the storage location                -   i. Item Code. These are defined by the 3M system,                    and may include for example: Adult Life Vest, Infant                    Life Vest, and Crew Life Vest. This list may be                    expanded in the future to include other items such                    as first aid kit, blankets, etc.                -   ii. Item Quantity. The quantity of this item                    expected in the storage location.

FIG. 23 is a flowchart showing one example manner in which a user suchas inspector 14 may inspect a vehicle such as an aircraft, where thevehicle profile (in this case the aircraft profile) is available withinan on-vehicle profile storage and retrieval system. First, inspector 14retrieves inspection device 10 (23A). Inspection device 10 may belocated in an area in proximity to the vehicle to be inspected, such asat a gate an airport, or at a maintenance facility. Inspection device10, in one embodiment, need not be located on the aircraft. Next, thevehicle profile is retrieved from the on-vehicle profile storage andretrieval system (23B). As mentioned above, the process by which thevehicle profile is retrieved is dependant on how the vehicle profile isstored (RFID versus computer system or otherwise). In the case where theprofile storage and retrieval system is an RFID chip, the profileinterrogation point would be an RFID tag, and the inspector wouldinterrogate the proper area (possibly marked as such), and receive thevehicle profile. Next, inspector 14 commences inspection of the vehicle(23C). The vehicle profile may be loaded and interpreted to provideinstructions regarding the inspection (an inspection protocol).Alternatively, inspector 14 may have been trained to execute a properinspection protocol, so no instructions need be provided on theinspection device. When the inspection is complete, inspector 14 mayfollow-up on exceptions discovered as part of the inspection (23D). Thisfollow-up may include, as the case may be, remedial activities, such asreplacing life vests found missing, or otherwise noting exceptionconditions for later reporting. In some implementations, once one ormore inspections is complete, inspection data may optionally be uploadedfrom the inspection device to another computer system for archival,analysis, report generation, or other purposes (23E). For example, ifthe inspection routine being used in FIG. 23 were being used to inspectan aircraft for life vests, the entity responsible for maintaining theaircraft may want reports indicating which aircraft were inspected andwhat the inspections showed. Inspection device 10, in some embodiments,includes the ability to store data resulting from an inspection of avehicle. Depending on the storage capacity of inspection device 10,resultant data sets from many inspection events could be stored forlater off-load.

FIG. 4 is a flowchart illustrating one example process in whichinspector 14 may use inspection device 10 to inspect for life vests 13using RFID tags 15. In this particular example, inspection devicelocation information is not used. In other words, analysis of whether alife vest is present or absent turns entirely on the presence of theRFID tag associated with a life vest, and there is no assessment ofwhether the life vest's expected location information is accurate. Withrespect to the system software diagram of inspection device 10 asrepresented in FIG. 3A or FIG. 3B, proximity coordination module 11would not be necessary for the type of inspection illustrated in FIG. 4and may be deactivated. This inspection method could be coupled with adefined inspection protocol, say seat-by-seat in ascending order, toproduce a very high degree of certainty that a life vest is present orabsent from beneath a given seat.

The inspection starts with the retrieval of an aircraft profile (401).The aircraft profile may be retrieved from host system aircraft profiledatabase 20, or may come from an interrogation of an aircraftprofile-containing RFID tag located on, or in proximity to, theaircraft. The profile may only be a subset of the entire profile—forexample it may only define the seating configuration of the aircraft,contain a graphic rendering of the aircraft (or contain enoughinformation such that a graphic rendering could be done by userinterface module 12), and include expected location information for eachlife vest with an associated RFID tag on the aircraft (if such expectedlocation information is not already present on the RFID tag itself).Receiving a profile at the start of an inspection may not be necessary,and the system, in one embodiment, accommodates the possibility that aprofile simply isn't available. There are several ways to proceed withan inspection in the absence of an aircraft profile. For example, ifexpected information location for a life vest is already on the RFIDtag, the profile is not critical. Alternatively, expected stateinformation is supplied by inspector 14 (when inspecting a row of threeseats, three life vest “pings” should come back, and the inspector iswatching for this), no information from profile 23 is necessary. The newprofile information is put into inspection device's aircraft profiledatabase 17.

Next, inspector initiates an aircraft inspection event (402). This isaccomplished, for example, by inspector 14 pressing a button oninspection device that activates an RFID tag interrogation routine, orotherwise signaling to the inspection device that an inspection is tobegin. Inspector then begins discreet inspection events by pressing atrigger on inspection device 10 when the device is aimed suitably at anaircraft seat or row of seats or other target area (403). Data comesback from the RFID tag affixed to a life vest or a life vest'spackaging, and is received by inspection device 10 (404). The inspectiondatabase 22 is updated with this information, along with any otherinformation on the tag itself (such as the date the life vest was placedin service or the expiration date of the life vest) (405). Validationand exception generation module 28 updates inspection device aircraftprofile database 17 with the life vests that have been inventoried, andfor example whether the life vest is expired. Validation and exceptiongeneration module 28 then requests user interface module 12 to updatethe user interface with this new set of information. In this way,feedback is presented to the user concerning the state of theinspection. At any point, inspector 14 may signal to inspection device10 that the inspection is complete (406). Until then, the process loopsback to the interrogation of life vest RFID tags (403) until the entireaircraft has been inspected. In another embodiment, it is not necessaryto initiate discreet inspection events associated with aircraft rows orother areas. Rather, the inspection event is started for the entireaircraft, and a user moves through the aircraft with the inspectiondevice constantly emitting an RF signal, and the inspection devicenoting any information read from RFID tags.

When inspector 14 indicates the inspection is complete (406), anexception report is generated (407) which inspector 14 or another personfollows-up upon (408). The exception report shows life vests thatrequire further inspection or analysis. If different life vests are putunder seats, this information is updated in the aircraft profile, andexpected location information possibly written to the RFID tag itself.The profile, updated to reflect the life vest configuration of thejust-inspected aircraft, is then sent back to host system aircraftprofile database 20, which synchronizes any updates (409). At thispoint, an inspection is complete. On implementations that do not rely ona centralized host system aircraft database, the profile information, inone embodiment, would be updated into an updated profile within theinspection device.

FIG. 5 is a flowchart illustrating another example process forinspection of an aircraft for missing, moved, or expired life vests. Theexample inspection detailed in FIG. 5 differs from the inspectiondetailed in FIG. 4 in that the inspection in FIG. 5 uses inspectiondevice location information at the time of an inspection event. This mayallow for automatic determination of whether a life vest has been moved,which may be indicative of tampering, thus warranting follow-up byinspector 14.

The inspection starts with the retrieval of an aircraft profile fromhost system aircraft profile database 20 (501). Alternatively, theaircraft profile may already be on in the memory of the inspectiondevice, or may be otherwise acquired, as, for example, by interrogatingan RFID tag that holds the aircraft profile. The profile may only be asubset of the entire profile—ideally it need only define the seatingconfiguration of the aircraft, contain a graphic rendering of theaircraft (or contain enough information such that a graphic renderingcould be done by user interface module 12), and include expectedlocation information for each RFID tag-associated life vest on theaircraft (if such expected location information is not already presenton the RFID tag itself). Receiving a profile at the start of aninspection is not necessary, and the system accommodates the possibilitythat a profile simply isn't available. There are several ways to proceedwith an inspection in the absence of an aircraft profile. For example,if expected information location for a life vest is already on the RFIDtag, the profile is not critical. Alternatively, expected stateinformation is supplied by inspector 14 (when inspecting a row of threeseats, inspector 14 makes sure three life vest “pings” come back from aninterrogation) and no information from profile 23 is necessary.Alternatively, an inspector could query seats and subsequently compareto profile information to determine exceptions (expired, missing, ormoved life vests).

Next, inspector initiates an aircraft inspection event (502). This isaccomplished, for example, by inspector 14 pressing a button oninspection device 10 to activate an RFID interrogation routine.Inspector then begins inspection events by pressing a trigger oninspection device 10 when the device is aimed suitably at an aircraftseat or row of seats or target area (503). Data is received from theRFID tag affixed to a life vest or a life vest's packaging, and isprocessed by inspection device 10 (504). Device 10 updates theinspection database 22 with this information, along with any otherinformation on the tag itself (such as the date the life vest was placedin service or the expiration date of the life vest).

Next, location information of inspection device 10 at the time ofinspection is determined (505). Inspection device location informationis determined by proximity coordination module 11, where the inspectiondevice location information is derived from external data feeds.Alternatively, inspection device location information could be derivedfrom a defined inspection protocol followed by inspector 14, asdiscussed above. When inspection device location information is based ona defined inspection protocol, it does not come from proximitycoordination module 11, and instead is deduced within validation andexception generation module 28.

There are several approaches to determining the inspection device'slocation information at the time of an inspection: by protocol(discussed previously), by the use of proximity tags, or by heuristicdata modeling techniques. Each of these approaches is considered in moredetail in upcoming discussion with respect to FIGS. 6A, 6B, and 6C.

The inspection device location information is used by validation andexception generation module 28 to determine various characteristics ofan inspection event. These various characteristics comprise expectedstate information for an inspection event, discussed earlier. Thespecific constituent data elements of expected state information is afunction of what is available to compare expected state informationagainst in order to derive meaningful information for inspector 14. Forexample, if the aircraft subject to inspection contains life vests forwhich expected location data is available (say for example, life vests #43, 25, and 58 are positioned beneath a row of three seats, which seatnumbers are 34A, 34B, and 34C), the expected state information wouldinclude the life vest numbers (43, 25, and 58) for the row. It would notnecessarily include expected seat numbers, nor would it necessarilyinclude the row number, as neither of these things could be validated.If, however, seat numbers or row numbers can be validated with anacceptable level of certainty at the time of inspection, then this datawould be part of the expected state information. Validation andexception generation module forms its expected state largely frominformation held within the aircraft profile held in inspection deviceaircraft profile database 17, and particularly the data sets within theaircraft profile 23 that define the locations where life vests areexpected. Expected state information also includes life vest expirationdate information, in the form of an expiration date, or the date inwhich the life vest was placed in service.

Ultimately, validation and exception generation module 28 uses what datait has available and forms a data set that represents the expected stateof the subject of an inspection event (an inspection event would be, asmentioned earlier, for example, the interrogation of a row). The actualdata that comes back from an RFID interrogation event, carried out byRFID interrogation module 29 and placed in inspection database 16, isthen accessed. A comparison is made between an inspection event'sexpected state, and its actual state. Matches and mismatches are notedin the inspection device aircraft profile database 17 (506).

Validation and exception generation module 28 may then request userinterface module 12 to update the user interface with the new set ofinformation in inspection device aircraft profile database 17. In thisway, feedback is presented to the user concerning the state of theinspection. At any point, inspector 14 may signal to inspection device10 that the inspection is complete (507). But until then, the processloops back to interrogation of the life vest RFID tags (503) until theentire aircraft has been inspected or the user indicates the inspectionevent is complete (“yes” at 507).

When inspector 14 indicates the inspection is complete (or the deviceindicates the inspection is complete) (yes at 507), an exception reportis generated (508) which inspector 14 or others follow-up upon (509).The exception report shows life vests that require further inspection oranalysis. If different life vests are put under seats, this informationis updated in the aircraft profile, and expected location informationpossibly written to the RFID tag itself. The profile, updated to reflectthe life vest configuration of the just-inspected aircraft, is then sentback to host system aircraft profile database 20, which synchronizes theupdates (510). At this point, an inspection is complete.

FIG. 6A through 6C are flow charts illustrating example sub-routinesthat could be used to determine location of inspection device in step505 in FIG. 5. The first, illustrated in FIG. 6A, is to use a definedinspection protocol that is followed by user 14. For example, a definedinspection protocol could be that inspector 14 first scans a first row,then a second row, and so forth. In such an inspection, the inspectiondevice location information can be ascertained by inspection device 10by looking up an internal representation of the protocol (6A1). Theprotocol may be defined on a one-aisle plane such that user 14 firstuses inspection device 10 to first inspect (interrogate) the starboardside of the aircraft, then the port side, then move on to row two and soforth. If there is more than one aisle on the aircraft, such that thereis a row of seats in the middle, this would be further defined by theprotocol. In this manner, when protocol instructs an inspection of row36, information received back is presumed to be from row 36. Based onthe inspection protocol being followed, the handheld device may be ableto ascertain its location on the aircraft. In one embodiment, aplurality of inspection protocols are contained within inspection deviceand inspector 14 may select among the protocols before starting aninspection. For example, inspector 14 may choose among two protocols,one whereby the aircraft is inspected starting in the rear of theaircraft, and another whereby the aircraft is inspected starting in thefront of the aircraft. When following a defined protocol inspection, andinterrogating row-by-row, a list of all life vest tags read, and notjust those tags in the currently-interrogated row, may be maintainedwithin inspection device 10, along with the location of inspectiondevice 10 as determined by protocol. Additional data may also be storedwithin inspection device 10, including for example the level of theradio frequency transmit power that was used to successfully interrogatethe tag (in certain embodiments the signal strength may be varied duringan interrogation event—for example the radio frequency signal strengthincreased during an interrogation event). At intermediate points in theprocess of the inspection, or perhaps more typically at the end of aninspection (defined inspection protocol is complete), or even real-time,the data collected may be processed with an algorithm executing oninspection device 10, or the data off-loaded to another computing systemand similarly analyzed. The algorithm would, in one embodiment,determine the probable location of each life vest successfullyinterrogated. For example, the algorithm may be programmed such that ifa particular life vest was originally installed in row 13, and the lifevest responded to interrogations of rows 12, 13, and 14, the probabilityis high that the life vest currently resides in its original, andcorrect, location. One skilled in the art will recognize thatembodiments of this approach to scanning could similarly be implementedin the absence of data defining where life vests are located on anaircraft. In such a scenario, an inspection may still be able todetermine, with acceptable accuracy, that there are likely enough lifevests on an aircraft to meet requirements, and/or that there are acorrect number and distribution of life vests, by row or section, forexample, on the aircraft. Alternatively, the protocol could be specifiedby the user 14 such that user 14 specifies to inspection device 10 therow user 14 is going to inspect or has just inspected.

FIG. 6B is a flow chart illustrating a method to determine locationinformation of inspection device 10 by interrogating a positional RFIDtag associated with, for example, a row of an aircraft (6B1). Thisinformation may be the row itself, or it may be a unique identifier of arow, which must then be looked up in a database to determine the actualrow number. Ultimately, however, the row is determined (6B2). One ofordinary skill in the art will recognize that other tags, oridentifiers, could be used to convey information concerning aninterrogation. For example, bar codes could be placed in proximity toevery expected RFID inspection location on an aircraft, and the bar codecould be scanned at the same time, or just before or after a row ofseats is inspected with RFID inspection device 10. For example, an RFIDtag could be placed on every row of the aircraft, and when interrogated,respond with the row number it is within. In this manner, when row 36 isinspected by inspection device 10, the RFID tag defining the rowresponds that the row is indeed the 36^(th), along with any life vestRFID tags.

FIG. 6C is a flow chart illustrating a method of determining inspectiondevice location information via a heuristic data analysis technique. Aheuristic data analysis technique in this context does not rely onlocation markers or other information specifically identifying thelocation of an inspection device at the point of an inspection. Rather,heuristic data analysis techniques analyze the data that has beengathered and tries to estimate where the inspection device likely islocated. A simple heuristic data technique is described and shown withrespect to FIG. 6C. First, data from a life vest inspection event isretrieved and reviewed (6C1). The data is next associated with lifevests. For a set of life vests identified per the life vest inspectionevent, a first life vest RFID tag is assessed to determine where itsexpected location information says it should be (6C2). This location ispresumed to be correct (6C3). The process is repeated for each life vestidentified in the life vest inspection event. If any life vest indicatesit should be in a different row or location, the entire row may bemarked as suspect, and then flagged for subsequent follow-up to confirmwhether there is an actual issue.

Other heuristic data analysis methods could be used to determineinspection device location information at the point of inspection. Forexample, a sliding window technique could be employed where a set ofsequential identifiers (N), read from the life vest's RFID tags, arecompared using a best-fit pattern match to the ordered set ofidentifiers within the database. The set of N recently read identifiersis “slide” through the database until the best matching position for thewindow is determined, thereby providing an indication of the currentlocation of the inspection device.

In other embodiments, combinations of protocol, location markers, andheuristic techniques may be combined. For example, in one embodiment, anRFID device is initially positioned in the aircraft at a given location.A marker tag there is scanned, providing the RFID inspection device withinitial coordinates within the aircraft. Inspection device then usesother techniques (protocol or heuristic or inertial) to determine wherethe inspection device is in relation to the marker tag.

An inspection of an aircraft for life vests may, in one or moreembodiments, be aided with an inspection device 10 executing life vestinspection code in the form of a computer program. Inspection device 10,in one embodiment, contains software including user interface module 12,that may generate various graphic user interfaces on screen 3 thatassist inspector 14 in inspecting life vests 13 on an aircraft. FIG. 7shows example information contained within aircraft profile 23 about theaircraft subject to inspection, which inspection device 10 may utilizeto graphically render all or a portion thereof on screen 3.Particularly, a seating arrangement is provided as part of the profile.For example, the seating arrangement can be used by inspection device 10to show example seat number 291 is located in a particular location onthe aircraft. FIG. 8 is an example user interface showing display window3000. Display window 3000 shows a series of visual indicia, in the formof small squares or rectangles, each corresponding to a seat on theaircraft that is being inspected. The individual squares correspond toseats on the aircraft, such as seat 3001 corresponds in this instance toseat 1A. The visual indicia are initially set to a first color, such asgray, that indicates that inspection device 10 has received noinformation to determine a particular life vest has been accounted for.The inspection is done with inspection device 10 by rows or partialrows. For example, row 3002 may be interrogated in two halves. ThoughFIG. 8 only shows a few rows of an aircraft, each expected life vest onthe aircraft may have corresponding visual indicia within the graphicuser interface, and the visual indicia may correspond to more than seatnumbers. For example, various locations on a plane may have spare lifevests, or may contain special life vests, such as for children. Theselocations are not generally under aircraft seats. These and otherlocations would be similarly represented in the user interface, andvisual indicia would similarly indicate the expected presence of a lifevest in these other locations.

While making the aircraft life vest inspection, inspector mayinterrogate rows or other locations where life vests are expected,visual indicia representing the locations of life vests on the aircraftas displayed on screen 3 may be updated to reflect the presence of theRFID tag associated with a particular life vest. FIG. 9 shows an examplescreen rendering wherein a visual indicium 3102, associated with seat 1Aon the aircraft, has been updated to reflect the presence of an RFID tagassociated with a life vest. In FIG. 9, the visual indicium is a lighthash mark. In one embodiment, the visual indicium is the color green.Inspector 14 may quickly and easily look at inspection device 10'sdisplay screen 3 to see the various life vests that have presumptivelybeen located. A second type of visual indicia may be used for instanceswhere the life vest is located, but is expired. Expired life vest visualindicium 3101 may be, for instance, the color yellow.

While inspecting the aircraft, inspector 14 may receive output fromdisplay screen 3 of inspection device 10 and quickly determine whichvisual indicia are either red (no RFID tag corresponding to the lifevest has been detected), or yellow (RFID tag corresponding to the lifevest having been located, but being expired or otherwise requiringfollow-up (for example, the life vest may not be in the correctlocation, or the life vest has been tampered with)).

FIG. 10 shows a rendering of an example screenshot that shows how thescreen scrolls as the inspector makes his or her way through theaircraft. Particularly, FIG. 10 is an example screen rendering a fewseconds after the rendering of FIG. 9, after inspector has moved closerto row 3204. Seat 3102 is now partially obfuscated by the border of thedisplay window, and the new row 3204 is beginning to appear at the topof the window. User interface module 12 provides a scrolling view of theaircraft and the inspection device's location within the aircraft byupdating display window 3000 whenever new information regarding a changein the location of inspection device 10 is available to user interfacemodule 12. User interface module 12 attempts to render display window3000 such that the next row to be interrogated is slightly above themiddle of display window 3000.

FIG. 11 is a flowchart showing an example process to update visualindicia representing locations of expected life vests in user interfacewindow 3000. Initially, user interface module 12 renders a graphicrepresentation of the aircraft, including at least enough detail todistinguish discreet areas in which a life vest may be expected toreside (3301). In other words, the graphic representation need not beoverly detailed, but it must at least show all of the places on anaircraft where life vests would traditionally be stored or located.

Next, user interface module 12 associates a visual indicium with eachexpected location of a life vest (3302). The expected locations of lifevests may come from a database pre-loaded with information aboutspecific life vests located in discreet locations. This database wouldbe loaded into inspection device aircraft profile database 17 as part ofthe aircraft profile 23, described above. Alternatively, if thisinformation is not available, user interface module 12 uses a defaultmapping of life vests within the aircraft that defines the minimum lifevest configuration necessary for the aircraft to make a flight.Additionally, default layouts of most aircraft, in the form of partialprofiles, may be stored within the inspection device 10. Thus, if nodetailed information about a given aircraft were available as part ofits profile, user interface module 12 would assign a visual indicium toeach seat in the aircraft, as defined by the default aircraft profile.

At this point, user interface module 12 is ready for an inspection tobegin. Inspector 14 may begin interrogating RFID tags 15 associated withlife vests 13 (3303). Information that comes back from an RFIDinterrogation at minimum includes a unique identifier, and mayadditionally include the RFID tag's last-registered location (forexample the seat number that the life vest was last registered under).If the location information is not included in the set of informationthat comes back from the RFID tag, this positional information may becontained within inspection device aircraft profile database 17, andthereby cross-referenced. There are other techniques, described ingreater detail above, that could be used to determine either the actualor expected location of a life vest (for example, via inspectionprotocol, via a separate RFID tag that includes location information, orvia heuristic methods). No matter the details of a particular technique(those skilled in the art may appreciate myriad techniques), proximitycoordination module 11, in one embodiment, determines the expectedlocation of the interrogated life vest 13 RFID tag 15, and passes thislocation information to user interface module 12 (3304) via inspectiondevice aircraft profile database 17. The location may either be theexpected location of the life vest, or it may be the actual location ofthe life vest, or it may be both. In one embodiment, it is both, whichallows for the identification of an exception condition wherein the lifevest is present, but is out of place. In an embodiment alreadydescribed, and as will be used for the illustrative purposes of thisexample, the location information is merely the expected position of thelife vest, contained within a life vest's RFID tag, in the form of aseat number. The expected position of the life vest would have beenregistered on the tag when the life vest was placed under a particularseat. For purposes of illustration, let us presume the informationreceived from the tag interrogation (3303) and the locationdetermination (3304) revealed the tag was #58237, and its expectedposition is under seat 7B. Validation and exception generation module 28determines a code for the given seat for which information is available.The code defines the inspection status of life vest. In one embodiment,the codes are as follows:

TABLE 1 Life Vest Inspection Code Meaning 1 RFID tag associated withlife vest responded without incident. 2 RFID tag associated with lifevest responded, but indicates the tag is expired. 3 RFID tag associatedwith life vest responded, but expected location does not equal actuallocation.

As will be evident to one skilled in the art, the use of life vestcondition codes other than 1 is dependant on the availability of data tosupport these codes. The non-existence of data to support life vestcondition codes 2 or 3 does not obviate the need or value of doing aninspection that only reveals life vest condition code 1s. However, lifevest condition codes 2 and 3 provide a more thorough inspection, andhave supporting processes described elsewhere in this specification.Preferred embodiments gather enough data to support all inspectioncodes. Validation and exception generation module 28 passes the locationcode, 7B, along with a condition code, in this case 1, indicating thelife vest was found, to user interface module 12, via inspection deviceaircraft profile database 17, which updates the visual indiciumassociated with seat 7B to be, in this case, from gray to green (3305).Other indicia useful to the user could be used alternatively or incombination with a color change. For example, an auditory signal couldbe sent when a life vest was properly located, and a different auditorysignal sent when a condition other than that represented by code 1 wassent (everything but code 1 requires follow-up by inspector 14 oranother authorized person, so an auditory indicium, such as a beep, mayindicate required follow-up).

The interrogation/inspection portion of the process is repeated (3306)until inspector 14 indicates the aircraft life vest inspection iscomplete, or all life vests that are expected have been accounted for,at which point the inspection is stopped (3307).

FIG. 12 is a flowchart showing an example operation of another aspect ofdisplay window 3000, namely the manner in which its graphicrepresentation of the interior of the aircraft scrolls as user 14 movesinspection device 10 within the aircraft, and as further represented inFIG. 10. The scrolling functionality is produced by first rendering agraphic representation of the aircraft (3401), the same as described inregard to FIG. 11. Next, each expected life vest is associated with avisual indicium within the graphic representation (3402), again the sameas with regard to FIG. 11. Next, the graphic representation and itscorresponding visual indicia are rendered onto the screen along withscroll bar 3205, with an initial position at the front of the aircraft(3403). The length of the scrollbar corresponds to the length of thegraphic representation of the aircraft, which corresponds to theaircraft itself. User 14 may move box 3206 along scroll bar 3205 toinspect the graphic representation of the aircraft, and moreparticularly the status of visual indicium associated with each lifevest 13 on the aircraft.

Next, inspection device 10 may determine its location within theaircraft (3404). As mentioned above, there are several methods toascertain this positional information. Some include the use of aninspection protocol, the use of positional RFID tags located at variouspositions throughout the aircraft, and the use of heuristic datamodeling techniques that determine the supposed position of theinterrogation device based on the life vest RFID tags beinginterrogated, and perhaps the order of the interrogation.

Inspection device location information is sent to user interface module12, which renders a new display window 3000 wherein the row justinterrogated is positioned slightly below midpoint of the Y-axis ofscreen 3, and the next row anticipated to be interrogated is positionedjust above the midpoint of the Y-axis of screen 3 (3405). These last twosteps are repeated via the “done with inspection” check (3406) whenevernew information describing the location of inspection device 10 isavailable, and in one embodiment, after each discreet inspection event.When the “done with inspection” check (3406) is true, the inspection maybe complete (3407).

If an aircraft profile containing the aircraft's seating configurationis not available, in one embodiment, inspection device 10 presentsinspector 14 with a series of questions that allow inspector 14 todefine the aircraft's seating position in an ad hoc manner. Theinspector is presented with a series of questions, such as the number ofrows, the number of aisles, the number of seats in a row, and so forth.There is then a dialog allowing the addition of alternative locationsfor life vests not associated with the seating arrangement (such asspare life vests and child life vests). FIG. 13 is a flow chartrepresenting an example manner in which the construction of aircraftprofile, graphically driven by user interface module 12, could work.

First, inspector 14 initiates configuration of a new aircraft event(3501). This would be done, for example, by pressing a button oninspection device 10, or if screen 3 is touch-sensitive, touching aportion of the screen indicating inspector 14's desire to manuallyconfigure the aircraft profile. Next, the user is presented with aseries of questions: How many rows in the aircraft? (3502); How manyaisles in aircraft? (3503); How many rows in a specific class section ofthe aircraft (class being first class, coach class, etc.)? (3504). Theclass question (3504) begins an iterative process by which each class isdefined, then subsequently information is gathered about that class ofseats. The remaining steps 3505 through 3508 encompass this iterativeprocess. Questions about seat configuration (a surrogate for mostinformation about life vest location configuration) continues untilinspector 14 indicates there is no further class in the aircraft (3508),at which point inspector 14 is able to add, in an ad hoc manner, otherinformation about where to expect life vests on the aircraft(3509-3512). If there are no further life vests expected on theaircraft, inspector 14 indicates such at 3509, and the aircraftconfiguration event is completed (3513).

FIG. 14 shows example attachment of RFID tag 15 to life vest 13. In oneembodiment, RFID tag 15 is placed on the exterior of life vest 13, as isillustrated by RFID tag 15A. Alternatively, the RFID tag may be place onpackaging into which the life vest is stored on an aircraft. Placing anRFID tag on packaging into which the life vest is stored is discussed ingreater detail below. In one embodiment, RFID tag 15 is placed on theinterior of the life vest, as illustrated by RFID tag 15B, asillustrated in a cutout view (101) of life vest 13.

FIG. 15 shows an exemplary view of a life vest 13 cut out. A first and asecond membrane (1101 and 1105) represent two layers of materialtypically used in life vest production. The membranes have an exteriorsurface (1107 and 1108) as well as an interior surface (1109). Theexterior surface is typically nylon. The interior surface is typically acoating of polyurethane (PU). The PU coating usually gives the life vestits substantially waterproof characteristics, while the exterior nylongives the life vest durability against exposure and abrasion. Flexiblecircuit substrate 1104 is comprised of an electrically insulatingmaterial having a suitable dielectric constant, such as fiberglass orplastic. An electronic circuit 1103, such as an application specificintegrated circuit (ASIC) or discrete logic components, is electricallyconnected to the antenna 1102 disposed on the flexible circuit substratelayer 1104.

There are several ways to ensure the RFID tag is securely within thelife vest. Three are discussed herein, but those skilled in the art willrecognize several approaches could be employed. One method is to use anadhesive. Adhesive layer 1106 exemplifies this approach. Adhesive layermay include various primers, or it may not be necessary at all if othernon-adhesive-based techniques, as described below, are employed.

A first example way to affix an RFID tag to the interior of a life vestincludes the use of a particular type of adhesive in adhesive layer1106, which is designed to work well in the unique operating environmentof the interior of the life vest 13.

As mentioned, interior surfaces of life vests typically comprise acoating of polyurethane (PU). PU has a low surface energy, which makesit a difficult surface to adhere to. Conventional acrylic-basedadhesives popularly used on RFID devices may not adhere well to PU orother low energy surfaces. Adhesion of RFID tag 15 to the interiorPU-based surface 1109 of life vest 13 may be accomplished, however, byusing a high performance adhesive designed to work with PU. A preferableadhesive system includes an adhesion promoter such as one known underthe trade designation “3M™ Adhesion Promoter 86A” and a pressuresensitive acrylic adhesive transfer tape or acrylic adhesive transfertape, such as the class of low surface energy laminating adhesives 300LSE available from 3M™, and specifically adhesives known under the tradedesignations, “3M™ 9485PC”, “3M™ 9934XL”, or “3M™ 9472E”.

Various adhesives were tested to adhere the RFID label to the interiorsurface of a life vest. The interior surface of the life vest compriseda thin, continuous, smooth coating of PU. Life vests used for the testwere from Eastern Aero Marine, Inc, 5502 NW 37th Avenue, Miami, Fla.33142, under the trade designation Adult/Child Life preserver, ModelUXF-35, FAA-TSO-C13f. The RFID tag used for the tests was purchased fromAlien Technology 18222 Butterfield Blvd., Morgan Hill, Calif. 95037,under the trade designation “ALL 9354-02 (M)”. The adhesives used in thetests are available from 3M™ of St. Paul, Minn., under the tradedesignations specified in Table 2, except for the Alien™ adhesive, whichwas pre-applied to the Alien RFID tag. The primer used is available from3M™ of St. Paul, Minn., under the trade designation “3M™ AdhesionPromoter 86A”. The primer layer may also be provided by a variety ofresins including but not limited to any hydroxy functional vinyl resin(e.g., VAGH from Union Carbide Corporation of Houston, Tex.), anycarboxyl functional resin (e.g., VMCH also from Union Carbide Corp.), orany amine functional resin. Polyamide primer layers such as MACROMELT6240 from Henkel Corporation of Dusseldorf, Germany, may also be used.These primers are best applied by dissolving in a suitable solvent(e.g., isopropyl alcohol) and wiping onto the area to be adhered. Otherways to prepare the PU surface could be used, including as anon-limiting example, a Corona treatment. Labels were adhered to theinside of the life vests behind the exterior text panel. Labels in thisposition did not exhibit any degradation in RFID-related performancethroughout the testing process. It was clear from initial testing thatlabels attached to a surface without the use of the primer did notadhere as well as the when the primer was used. This was true for everyadhesive tested.

Life vests 13 were tested using the following inflation test to assesshow well the adhesives work during real world use. The inflation test isan FAA approved test for life vests and is conducted on life vests every5 or 10 years, depending on the type of vest. The life vests werepressurized to 2-4 PSI (0.014-0.028 MPa) and held under pressure for 1-2minutes. Observations were made and the vest then deflated, folded, andpacked as they would be in preparing for placement within an aircraft.This process was repeated 5 times, which is typical of the number oflife vest test cycles the life vest may undergo in its operational life.All RFID tags functioned after the test. Further, no life vest leakedair after any test. However, RFID tags adhered to the life vest'sinterior surface without the use of primer detached from the life vestsurface and became free-floating within the life vest cavity upon lightshaking in some cases, and no shaking in others.

Adhesives were applied to a polyester backing (the same as would befound on an RFID tag), then adhered to the PU surface of one-inch stripsof life vest material. Both a 5-minute and a 72-hour, 180-degree roomtemperature peel test were performed as per ASTM-D3330 test method A onthe different adhesive systems mentioned above. Each test was performedthree to five times to arrive at an average peel strength value. Table 1summarizes results of the testing.

TABLE 2 5 Min Peel Strength, 72 Hr Peel Strength Primer Adhesive averageoz./in. (N/m) average oz./in. (N/m) No 3M ™ 8616   3 (32.8)   8 (87.6)No 3M ™ 8617   29 (317.4) NT* No 3M ™ 9472LE   16 (175.1)   25 (273.6)No 3M ™ 8672   1 (10.9)   3 (32.8) No 3M ™ 9485   13 (142.3)   36(394.0) No Alien “ALL 9354-02 (M)”   9 (98.5)   27 (295.5) No None NT*NT* Yes 3M ™ 8616   31 (339.3)   53 (580.1) Yes 3M ™ 8617  ≧120 (1313.5) ≧120 (1313.5) Yes 3M ™ 9472LE   52 (569.2)   47 (514.4) Yes 3M ™ 8672  49 (536.3)   60 (656.7) Yes 3M ™ 9485   49 (536.3)   64 (700.5) YesAlien “ALL 9354-02 (M)”   45 (492.5)   57 (623.9) No Ultrasonic weld NT*NT* *NT = not tested

A second example way to affix an RFID tag 15 to an interior surface oflife vest 13 is by the use of high frequency welding. This was achievedusing the following technique. The RFID tag was placed on the inside ofthe vest and held in position using the adhesive already on the tag assupplied by Alien™. A section of PU-coated nylon fabric two incheslarger (overlapping) than the RFID tag in the X and Y direction was thenplaced centrally over the RFID tag. The section of PU-coated fabric wasoriented in such a way that the PU-coated surface of the cover and thePU surface of the vest were adjacent to each other. The assembly wasthen placed under the HF welding horn of a FIAM Welding machine Model #3005 LF, manufactured by, FIAB System AB, S-453 29 Lysekil, Sweden.Sufficient energy (power and time) was applied to the horn to weld thePU layers of the two fabrics together. This process was repeated on eachof the four sides of the patch, thus enclosing the RFID label in the HFwelded patch.

A third example way to affix an RFID tag 15 to an interior surface oflife vest 13 is through the use of mechanical fasteners, such as hookand loop, which have been adhered to a surface of the life vest.Refastenable fastening devices of the hook and loop-type are currentlyused widely in a great number of situations. Such refastenable fasteningdevices have been used in clothing, disposable articles, and variousmiscellaneous articles such as safety belts and the like. Such devicesare used when it is desirable to create a refastenable bond between twoor more articles or between several surfaces of the same article. Incertain applications, these refastenable fastening devices have replacedconventional adhesives, buckles, zippers, buttons, snaps, tie fasteners,and sewing.

A popular type of mechanical fastener currently in wide use whichutilizes mechanical entanglement to create a refastenable bond is soldunder the trademark “VELCRO”. VELCRO fastening devices are described ingreater detail in U.S. Pat. No. 2,717,437, U.S. Pat. No. 3,009,235, U.S.Pat. No. 3,266,113, U.S. Pat. No. 3,550,837, U.S. Pat. No. 4,169,303,and U.S. Pat. No. 4,984,339. Other types of mechanical fasteners aredescribed by 3M in U.S. Pat. No. 4,894,060, U.S. Pat. No. 5,870,770,U.S. Pat. No. 5,679,302, U.S. Pat. No. 6,000,106 and U.S. Pat. No.6,814,912.

Mechanical fasteners utilize two components, a male component and afemale component. The male and female components are often referred toas the hook and loop components, respectively. The hook componentconsists of a fabric which contains a plurality of resilient, upstandinghook-shaped elements. The female component of the fastening deviceconsists of a fabric containing a plurality of upstanding loops on itssurface. When the hook component and the loop component are pressedtogether in a face-to-face relationship to close the fastening device,the hooks entangle the loops forming a plurality of mechanical bondsbetween the individual hooks and loops. When these bonds have beencreated, the components will not generally disengage under normalconditions. This is because it is very difficult to separate thecomponents by attempting to disengage all of the hooks at once. However,when a gradual peeling force is applied to the components, disengagementcan be easily effected. Under a peeling force, since the hooks arecomprised of a resilient material, they will readily open to release theloops.

A fourth example way to locate an RFID tag 15 to an interior surface oflife vest 13 is to place the RFID tag inside of the life vest at thetime of manufacture, not adhered or otherwise affixed to any interiorsurface of the life vest. RFID tag 15B would then be free to movearound. This free movement would not necessarily pose problems asinitial placement and subsequent folding during the manufacturingprocess may adequately orient the tag. Unfolding of life vest 13 usuallydoes not take place during an inspection process. Rather, the life vestis typically unfolded during a re-certification process, which canhappen 5-10 times in the life of the vest. It is possible, however, thata freely moving RFID tag 15B could end up in a position within life vest13 wherein its ability to send or receive radio signals is diminished orcompromised. This might happen, for example, if RFID tag 15B weresituated in close proximity to a radio insulation or reflectioncomponent, such as life vest inflation mechanism 102. Life vestinflation mechanism 102 typically contains a CO2 cartridge made ofmetal. This and other components of a life vest may prevent RFID tag 15Bfrom performing as intended. Free movement may be restricted by thecreation of an interior compartment, or cavity, within the life vestthat restricts the movement of RFID tag 15B.

As mentioned above, an alternative to placing RFID tag 15 on theinterior or exterior of life vest 13 is to place it on the life vestpackaging. When placed on life vest packaging, the use of a particulartype of RFID tag, in a particular configuration, may render the lifevest packaging tamper evident and enable remote identification ofpackages that may have been tampered with. Particularly, an RFID tagplaced across the tear path of a package inside of which the life vesthas been placed will be destroyed or rendered inoperable when thepackage is opened.

FIG. 16 shows an example configuration of life vest 13, folded (13B) andplaced within package 2101. RFID tag 15 is situated on package 2101 in amanner such that it not practical to gain access to the life vestwithout compromising RFID tag 15. Package 2101 includes tear tag 2102.Not all life vest packaging has such a rip tag. There are generally twotypes of aircraft life vest packages: 5-year and 10-year. A 5-yearpackage is usually composed of a flexible polymer such as polyethylene,and includes a tear tag, such as tear tag 2102 made of a tear-resistantplastic, which is attached to surface of the package, and the packageclosed by stitching the surfaces together. Pulling tear tag 2102 openspackage 2101 by producing a uniform slit across the package. A 10-yearpackage is usually made from the same material as the life vests: nylon,coated with PU. To assist in opening a 10-year package, a notch is cutinto the fabric so a tear can propagate in the desired direction.Package 2101 is a 5-year type, and further life vest package examplespresented herein are drawn generally to a 5-year type of package. Thisfocus on a 5-year type package is for illustrative purposes only. Aswill be appreciated by one skilled in the art, this invention may beeasily applied to a 10-year type package, and any existing orto-be-conceived packaging solution that includes a mechanism foraccessing the package's contents along a pre-defined region of thepackage's membrane.

FIG. 17 shows a more detailed view of example package 2101. Inparticular, RFID tag 15 is shown, and perforation 2103 in RFID tag 15 issituated such that its apex intersects a tear line 2104 that defines aneventual opening line, such that by pulling tear tag 2102, the resultinglateral slit will compromise the RFID tag. The compromise of the RFIDtag may take several forms, but in a preferred embodiment, the RFID tagantenna is separated into two parts and thereby rendered inoperable. Ifusing life vest inspection methods described elsewhere in thisspecification, the inoperative RFID tag would result in the associatedlife vest being considered missing or compromised, and would compelsubsequent follow-up, which would likely mean physical inspection. Ifthe package were found to be compromised, the life vest in the packagewould be re-packaged (if the life vest was found to be in satisfactorycondition). Alternatively, if a package were found to be compromised,then a replacement package containing a life vest would be substitutedfor the compromised life vest.

The inoperability of the RFID tag, in one embodiment, is the result ofthe RFID tag's antenna being separated from the RFID tag's integratedcircuit. This may be accomplished by situating the RFID tag upon thetear line 2104 in a way such that the slit will either disconnect theRFID tag's antenna, or disconnect a sufficiently large portion of itthat the practical result is the same.

One or more tear propagation points (small slits or holes) in flexiblecircuit substrate 1104 can significantly enhance the sensitivity of theRFID tag to compromise. FIG. 18A through 18D show examples ofpre-slitting flexible circuit substrate 1104. RFID tag 15A showsflexible circuit substrate 1104 without any tear propagation points. Itincludes antenna 1102 and integrated circuit 1103. Antenna 1102 andintegrated circuit 1103 repeat in example views of RFID tags 15B, 15C,and 15D, but for clarity they are not explicitly specified with respectto the figure. RFID tag 15B shows flexible circuit substrate 1104 withtwo lateral notches or slits, 2201, that, when connected, intersectintegrated circuit 1103 at approximately a 90 degree angle. A tear downthis slit would compromise the RFID device by destroying the integratedcircuit antenna interface. RFID tag 15C shows tear propagation points,in this case slits 2201, variously positioned along a first edge offlexible circuit substrate 1104, with a similarly situated set of slitspositioned along the flexible circuit substrate's second edge. The slitsdo not need to be aligned, and there need not be slits on both edges—theslit is of particular use on the edge closest to the start of the tearpropagation point. Putting slits on both edges makes application of thetags less error-prone (there are multiple orientations that will work).A tear across any of these slits would compromise the antenna. For someRFID tags, the compromise of the antenna will render the RFID deviceinoperable. For other RFID devices, the device may still work, but workdifferently. For such RFID devices that are not rendered inoperablemerely due to antenna compromise, the integrated circuit is designedsuch that it will not function if any antenna circuit is broken. RFIDtag 15D shows an alternative configuration of the slits, such that theyrun substantially parallel to the longer axis of RFID tag.

915 MHz Alien™ (of Morgan Hill, Calif.) Squiggle™ ALL-9338-02 EPC RFIDtags were used in testing various tear propagation points, or slitconfigurations. RFID tags were attached to five and ten year packagesusing a pressure sensitive adhesive that came on the RFID tag, and anadhesion promoter (3M™ A86, mentioned above) if needed. FIGS. 19A and19B show various placement positions of RFID tags on life vest packages.Specifically, FIG. 19A shows placement on a five year vest, and FIG. 19Bshows placement on a ten year vest. On the five year vests (FIG. 19A),the tags were placed as follows: A—on the exterior surface of thepackage across the tear line (2104), on top of the stitched on tearlabel 1943 (such tear labels allow a user to grip a member thatfacilitates the tear in the tear propagation line 2104, and is availableon certain life vest packages); B—on the outside of the package on topof the stitched tear line (2104), away from the stitched tear label1943; C—placed on an interior surface of the package before it isstitched together, located on the tear propagation line 2104; D—placedon the outside of the package, but underneath the tear label 1943. Onthe ten year vests (FIG. 19B), the tags were placed as follows: E—on theexterior of the package across the tear line 2104; F—placed on theinterior of the package before the package is sealed via high frequency(HF) weld. Testing of RFID tags on life vest packages involved firstputting slits on the RFID tag's flexible circuit substrate 1104 (ifneeded). Second, the RFID tag was placed on the life vest package suchthat a pair of slits approximately aligned with tear line 2104. Thespecific mechanism of attaching is described earlier, but in all casesthe attachment mechanism was sufficiently strong as to hold the RFID tagin place throughout the testing. Third, the RFID tag was tested toensure it operated properly, and was readable after attachment to thepackage but before opening the bag. Fourth, the package was opened alongtear line 2104 using the appropriate mechanism (either tear tag 2102 ora tear notch). The RFID tag test passed if, upon package opening, theRFID tag was compromised and thereby rendered inoperable. Table 3 showsthe results of the testing.

TABLE 3 Location Slit Vest (see FIG. 19A ((Y)es/ operating Openingrendered tag Test ID and 19B) (N)o) life (yrs) inoperative AAMD-1 E Y 10True AAMD-2 E N 10 False AAMD-3 E N 10 False AAMD-4 F Y 10 True AAMD-5 AY 5 True AAMD-6 C Y 5 True AAMD-7 B Y 5 True AAMD-8 D Y 5 True AAMD-9 BN 5 True

Most configurations passed the test (that is, the RFID tag was notreadable after opening the bag, which is indicated by a “true” in thelast column of Table 3). Three tests did not use a pre-slit RFID tag.The first, AAMD-2, used an adhesive that was later determined to bepoorly suited for the application. AAMD-3 used 3M™ PSA 8617 with thesurface treated with 3M primer A86 (described further above). The RFIDtag adhered well to the surface and did not allow the package to beopened by normal forces at the tag across tear line 2104. With no slits,the tear strength of the RFID tag (with a polyester backing) wassufficiently high such that either the adhesive failed before the RFIDtag's flexible circuit substrate was compromised, or the RFID tag'sflexible circuit substrate prevented the package from being opened. Theother test made with no pre-slitting was AAMD-9. In this test, thepackage was a 5-year type, with a tear line comprised of stitching. TheRFID tag failed, but the failure was likely due to the fact that slitswere, in effect, punched in the RFID tag's flexible circuit substrate bythe stitching process, and these slits or holes acted as rip propagationpoints. Generally, if no rip propagation points (holes or slits) exist,then it is necessary to use a backing material for the flexible circuitsubstrate that is weak enough to tear. Such a layer could, for example,be paper.

Testing

As mentioned earlier, RFID inspection methods were tested on a Boeing737 and 747, a McDonnel-Douglas DC9 and 10, and an Airbus A300. RFIDtags were placed between the underside of the seat bottom and the lifevest for each seat in five contiguous rows within each aircraft. Theimpact of metal seat pans on interrogation using two transmit powers, 18dBm and 19 dBm, was tested on a DC10 that did not initially have metalpans in its seats. A first set of interrogations was completed in thisnative state, then with installed metal plates under each seat cushion.FIG. 20A through FIG. 20H summarize aspects of the test methodology andresults.

FIG. 20A is an exemplary user interface as might be displayed by aninspection device guiding a user inspecting the aircraft. The screenshows a graphical representation of the seating configuration of theaircraft being inspected. Particularly, numbered boxes represent seats,and form rows and aisles. The user interface, in this example, is anexemplary screenshot captured at the start of an inspection. Positionalinformation regarding the inspection device, in this example, isgarnered from an inspection protocol, which is presented to the user viathe user interface. In other words, inspection device's display screenadvises the user of the order in which to scan (“Press Trigger to Scan25A,B.” After an inspection event has concluded, for example by the userpressing and releasing a trigger on an inspection device, instructionson the inspection device may then read, “Press Trigger to Scan 26A,B.”

FIG. 20B shows how testing of metal plates/radio transmit power on aDC10 was executed. A user interrogated rows 20B1, and received signalsback from seats 20B2, and moved per an interrogation event orderspecified by order 20B3. FIG. 20C is a key to assist in reading resultsof the testing, which is summarized in the table of FIG. 20D. FIG. 20Dsummarizes the absolute value read range for each interrogation event attransmit powers of 18 and 19 dBm, respectively. FIG. 20E is a graphicillustration of median read range achieved when metal pans are presentunder seats, using a radio transmit power of 18 dBm. FIG. 20F is agraphic illustration of median read range achieved when metal pans arenot present under seats, using a radio transmit power of 18 dBm. FIG.20G is a graphic illustration of median read range achieved when metalpans are present under seats, using a radio transmit power of 19 dBm.FIG. 20H is a graphic illustration of median read range achieved whenmetal pans are not present under seats, using a radio transmit power of19 dBm.

Various implementations and embodiments of the invention have beendescribed. For instance, methods of inspecting an aircraft, andsupporting systems and graphic user interfaces have been described.Further, various configurations concerning the placement of an RFID tagon a life vest have been described, as have RFID tags placed onpackaging and prepared in such a way that the life vest package istamper evident. Nevertheless, it is understood that variousmodifications can be made without departing from the invention.Accordingly, these and other embodiments are within the scope of thefollowing claims.

1. An article comprising: a sealed package made of a membrane; apersonal floatation device disposed within the sealed package; anopening mechanism for opening the package along a pre-defined area ofthe membrane; an RFID device comprising a flexible substrate having anantenna and an integrated circuit disposed thereon; wherein the RFIDdevice is affixed to the membrane of the sealed package to span an areaof the package along the pre-defined area of the membrane so thatopening the sealed package will mechanically compromise a portion of theflexible substrate.
 2. The article of claim 1, wherein the personalfloatation device is a life vest.
 3. The article of claim 1, wherein theopening mechanism is a means for opening the package along a pre-definedarea of the membrane.
 4. The article of claim 1, wherein themechanically compromised portion of the flexible substrate includes theantenna.
 5. The article of claim 1, wherein the mechanically compromisedportion of the flexible substrate includes a circuit that is not theantenna.
 6. The article of claim 1, wherein the opening mechanism is anotch in the membrane.
 7. The article of claim 1, wherein the openingmechanism is a tear strip affixed to the membrane.
 8. The article ofclaim 1, wherein the flexible circuit substrate is configured with tearpropagation points.
 9. The article of claim 8, wherein the tearpropagation points are holes.
 10. The article of claim 9, wherein theholes are substantially rectangular in shape with a length and a width,and wherein the length is at least twice the width.
 11. The article ofclaim 8, wherein the tear propagation points are slits.
 12. A method ofmanufacturing a tamper-evident package made of a membrane comprising:placing a life vest inside of the package; determining the package'stear path; and affixing an RFID device comprising a flexible substratehaving an antenna and an integrated circuit disposed thereon to themembrane such that part of the flexible substrate is on both sides ofthe tear path so that when the package is opened along the tear path theflexible substrate is mechanically compromised.
 13. The method of claim12, wherein the tear path is defined by a notch in the package.
 14. Themethod of claim 12, wherein the tear path is defined by a rip cordaffixed to the membrane.
 15. The article of claim 1, wherein the openingmechanism is stitching.